DERRY TOWNSHIP, Pennsylvania — The mid-morning sun danced cleanly off the calm waters of Keystone Lake, casting a bright sheen over a scene that feels entirely unstuck from time.

Along the shoreline, kayakers glide across the glass-like water. Fishermen sit quietly by the causeway, casting lines in hope of a bite. Under the shade of the locust, maple, tulip, and oak trees, families crowd around picnic tables, sharing peanut butter and jelly sandwiches from home as they shake off the heavy heat of a Pennsylvania summer.